Tall cell variant: an aggressive form of papillary thyroid carcinoma.

Twenty-four cases of the tall cell variant (TCV), a subset of papillary thyroid carcinoma, were identified in a group of 624 patients with thyroid cancer. All pathology specimens were reviewed, and each patient's carcinoma was categorized according to characteristics on presentation, local recurrence, distant metastases, follow-up, and tumor-related mortality. The TCV group was compared with a historical control group (Mazzaferri and Jhiang: 1355 patients). The TCV group had a statistically higher percentage of stage 3 and 4 carcinoma, extrathyroidal invasion, and tumor size less than 1.5 cm than the control group. There was no statistical relationship between age greater than 50 years and stage in the TCV group. No relationship could be found between TCV histology and recurrence or mortality. These findings, combined with those of studies that link stage on presentation to poor outcomes, have led to our conclusion that TCV is an aggressive malignancy warranting appropriate treatment and close follow-up.